title: Comparison of manufactured and black carbon nanoparticle concentrations in aquatic sediments.
abstract: In this paper, we show that concentrations of manufactured carbon-based nanoparticles (MCNPs) in aquatic sediments will be negligible compared to levels of black carbon nanoparticles (BCNPs). This is concluded from model calculations accounting for MCNP sedimentation fluxes, removal rates due to aggregation or degradation, and MCNP burial in deeper sediment layers. The resultant steady state MCNP levels are compared with BCNP levels calculated from soot levels in sediments and weight fractions of nanosized fractions of these soot particles. MCNP/BCNP ratios range from 10(-7) to 10(-4) (w:w). This suggests that the often acclaimed effect of MCNPs on organic pollutant binding and bioavailability will likely be below the level of detection if natural BCNPs are present, even if binding to MCNP is one to two orders of magnitude stronger than to BCNPs. Furthermore, exposure and toxic effects of MCNPs in sediments and soils will be negligible compared to that of BCNPs.
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen, The Netherlands. bart.koelmans@wur.nl
authors.forename: A A
authors.initials: AA
authors.lastname: Koelmans
authors.forename: B
authors.initials: B
authors.lastname: Nowack
authors.forename: M R
authors.initials: MR
authors.lastname: Wiesner
mesh_terms: D000327:Adsorption; D004784:Environmental Monitoring / Q000379:methods; D005618:Fresh Water; D019015:Geologic Sediments / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D053260:Soot / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D037742:Nanotubes, Carbon; D012989:Soil Pollutants; D053260:Soot; D014874:Water Pollutants, Chemical